UNIVERSITY    OF    CALIFORNIA     AGRICULTURAL   EXPERIMENT  STATION 

~*.  .  -^-    ~~     .«._._..._....-  BENJ.    IDE   WHEELER,    President 

COLLEGE   OF   AGR  CULTURE 

^w      w.-^..-    wr     "«n,v«t      writ.  THOMAS    FORSYTH    HUNT,    Dean  and  Director 

BERKELEY  H.    E.    VAN    NORMAN,    Vige-Director    and    Dean 

University  Fart."   School 


CIRCULAR  No.  199 

May,  1918 


ONION  GROWING  IN  CALIFORNIA 

By  STANLEY  C.  ROGERS 


CONTENTS 

PAGE 

Introduction 1 

Onion  Producing  Sections  in  California 2 

Cost  of  Production,  Yields  and  Prices  Received 2 

Cultural    Requirements 3 

Soil    3 

Moisture 3 

Climate 3 

Preparation   of  the   Soil 3 

The  Onion  as  a  Market  Garden  Crop 4 

Methods  of  Propagating 4 

Planting 5 

Transplanting  to  the  Field (> 

Irrigation 8 

Cultivation 10 

Breaking  Down  the  Tops 10 

Harvesting 11 

Storage  13 

Onions  as  a  Truck  Crop 14 

Varieties  13 

Onion   Seed  Production 17 

Crop  Troubles  20 

Onions  have  always  been  one  of  the  most  important  vegetable 
crops  in  California  and  as  early  as  1874  there  was  considerable  interest 
in  their  production.  From  the  years  1900  to  1915,  inclusive,  the 
amount  planted  in  this  state  varied  from  2500  to  4500  acres  per  year. 

As  reported  by  the  Bureau  of  Crop  Estimates,  the  onion  acreage 
in  California  for  the  years  1916  and  1917  are  as  follows : 

1916  1917 

Bermuda  onions   570  1,435 

Midsummer  or  intermediate 1,000  1,500 

Late   or   storage   onions 4,300  9,000 


According  to  the  estimates  of  the  U.  S.  Department  of  Agriculture, 
California  was  the  largest  onion-producing  state  for  the  years  1916 
and  1917. 

ONION-PRODUCING    SECTIONS    OF    CALIFORNIA 

San  Joaquin,  Contra  Costa,  Sacramento,  Imperial,  Riverside,  and 
Santa  Barbara  counties  are  the  principal  onion-producing  sections  in 
California.  Aside  from  these,  onions  are  grown  throughout  the  entire 
state,  and  there  is  probably  not  a  market  garden  in  California  which 
does  not  produce  this  crop  at  some  season  of  the  year. 

COST    OF    PRODUCTION,    YIELDS,    AND    PRICES    RECEIVED 

The  cost  of  producing  onions  is  dependent  upon  the  character  of 
the  soil,  method  of  cultivation,  season,  acreage,  and  experience  of  the 
grower,  and  varies  from  $70  to  $125  per  acre,  with  an  average  cost 
of  $80,  exclusive  of  land  rental  and  fertilizing.  The  following  cost  per 
acre  data  have  been  secured  from  several  experienced  growers,  and 
at  the  University  Farm  garden : 

Plowing   12   in.   deep $3.00 

Harrowing  and  packing 1.00 

Seed   4.00 

Growing  plants   1.00 

Transplanting  20.00 

Irrigating    (four  times)  10.00 

Hoeing  and  weeding 25.00 

Harvesting  and   sacking 20.00 

$84.00 

The  yields  of  onions  vary  from  50  to  700  sacks  per  acre,  a  sack  of 
onions  weighing  from  100  to  105  pounds.  Where  this  crop  is  grown 
by  the  intensive  method,  production  varies  from  300  to  500  sacks  per 
acre,  with  occasionally  larger  yields.  Where  the  onions  are  produced 
on  large  tracts,  the  normal  yield  is  from  200  to  300  sacks  per  acre. 

The  price  of  onions  varies  more  than  any  other  vegetable.  As  a 
rule,  the  highest  prices  are  paid  during  the  winter  and  spring,  and 
the  lowest  during  mid-summer  and  fall.  Occasionally  this  vegetable 
will  bring  35c  to  40c  per  sack,  while  during  other  years  the  price  is 
from  $6  to  $8  per  sack.  The  average  price  for  the  summer  crop  varies 
from  75c  to  $1  per  sack,  and  the  winter  and  spring  crop  will  generally 
command  from  $1  to  $3  per  sack.  As  a  large  part  of  the  California 
crop  is  shipped  to  states  east  of  here,  the  winter  and  spring  quotations 
are  dependent  largely  upon  the  supply  in  the  eastern  store-houses, 
especially  in  those  of  Texas. 


CULTURAL    REQUIREMENTS 

Soils. — The  choice  of  suitable  soil  is  one  of  the  fundamental  factors 
in  onion  growing.  The  soil  best  adapted  for  this  crop  is  one  which 
is  retentive  enough  under  cultivation  to  keep  sufficient  moisture  about 
the  roots,  and  friable  enough  to  be  easily  cultivated  and  to  allow  the 
proper  expansion  of  the  bulb.  It  should  be  rich  in  organic  matter  and 
the  minerals,  for  it  is  impossible  to  grow  a  satisfactory  crop  of  onions 
on  a  soil  of  poor  quality.  A  heavy  adobe  or  clay  is  very  expensive  to 
work  and  is  so  compact  that  it  is  sometimes  impossible  to  produce 
onions  of  desirable  size  and  shape.  Soils  of  a  very  sandy  nature  are 
liable  to  be  deficient  in  the  essential  food  materials,  and  it  is  difficult 
to  retain  sufficient  moisture  for  the  plants,  even  where  irrigation  is 
practiced.  When  growing  this  crop  for  the  early  spring  markets,  the 
ideal  soil  will  be  lighter  in  character  than  one  producing  fall  crops. 
The  most  desirable  class  of  soil  is  either  a  light  loam  or  peat,  rich  in 
plant  food  and  retentive  of  moisture.  The  most  undesirable  soils  are 
adobe  and  coarse  sand  or  gravel. 

Moisture. — Onions  require  large  amounts  of  soil  moisture  from 
the  time  of  planting  until  they  are  maturing  and  the  relation  between 
the  moisture  supply  and  the  production  of  onions  is  vitally  important. 
As  this  is  one  of  the  most  shallow-rooted  vegetables,  the  field  practice 
should  be  such  that  the  moisture  will  be  retained  within  one  to  three 
inches  of  the  surface  throughout  the  entire  growth  of  the  plant.  The 
plants  will  stand  an  excessive  amount  of  water  with  less  injury  than 
when  the  supply  is  deficient.  From  the  time  the  crop  is  beginning  to 
mature  until  it  is  harvested,  the  amount  of  soil  moisture  necessary  is 
much  smaller  than  during  the  other  stages  of  growth,  as  an  over- 
abundance during  this  period  will  produce  onions  which  are  watery, 
and  are  of  poor  keeping  quality. 

Climate. — The  onion  is  one  of  the  most  hardy  vegetables  grown 
and  is  so  resistant  to  cold  that  it  is  produced  during  the  season  of  the 
year  when  many  of  the  other  vegetables  would  be  killed.  If  given 
plenty  of  moisture  it  will  endure  the  heat  well,  although  it  grows  most 
luxuriantly  in  moderate  temperatures.  At  the  University  Farm  gar- 
den, during  the  winter  of  1916,  small  onion  plants  in  the  seed-beds 
withstood  a  temperature  of  20°  F.  apparently  without  injury. 

PREPARATION    OF   THE    SOIL 

The  preparation  of  the  field  and  its  condition  at  planting  is  often 
the  direct  cause  of  the  success  or  failure  of  the  entire  crop.  The  first 
essential  requirement  is  that  the  field  be  entirely  free  from  weeds,  and 


at  the  time  of  planting  the  earth  should  be  moist  up  to  the  surface  and 
in  as  fine  a  physical  condition  as  possible.  The  experienced  grower 
realizes  the  importance  of  a  good  seed  bed  so  that  the  field  is  worked 
very  carefully  previous  to  planting. 

A  large  percentage  of  the  crop  is  grown  in  California  without 
fertilization.  This  is  especially  true  throughout  the  delta  sections. 
When  the  crop  is  being  grown  in  the  market  garden,  a  large  quantity 
of  manure  is  used  a  short  time  before  planting,  applications  being- 
made  at  the  rate  of  from  fifteen  to  thirty  tons  per  acre.  The  manure 
should  be  put  on  long  enough  before  planting  so  that  it  may  be  com- 
pletely rotted  by  the  time  the  field  is  to  be  used,  and  it  is  preferable 
to  apply  well-rotted  manure  rather  than  that  which  is  hauled  directly 
from  the  stable,  for  otherwise  the  litter  which  it  contains  will  have  a 
tendency  to  keep  the  soil  open,  allowing  it  to  dry  around  the  young 
tender  plants;  the  liability  of  weed  infection  is  much  greater  in  case 
of  fresh  manure  than  with  well-rotted  manure.  It  is  not  customary  to 
plow  under  the  manure  as  deeply  as  would  be  advisable  in  growing 
other  vegetables. 


THE  ONION  AS  A  MARKET  GARDEN  CROP 

Method  of  Production. — When  growing  onions  in  the  market 
garden,  the  seed  is  generally  sown  in  seed  beds  and  the  young  plants 
transplanted  to  the  field.  This  method  has  two  advantages  over  seed- 
ing in  the  field ;  onions  which  are  transplanted  will  generally  produce 
a  more  even  crop  and  the  stand  will  be  more  uniform  than  if  the  seed 
is  sown  directly  in  the  field.  The  crop  will  occupy  the  field  one  to 
two  months  less  time,  which  is  of  considerable  importance  where  high 
rental  is  paid,  as  it  may  give  the  grower  a  chance  to  produce  one 
more  crop  than  he  otherwise  could. 

There  are  two  forms  of  seed  beds  used,  open  beds  and  hotbeds. 
The  former,  which  are  the  most  common,  are  made  three  to  five  feet 
wide  and  eight  to  twelve  feet  long ;  a  ridge  of  earth  six  to  eight  inches 
high  and  one  foot  in  width  at  the  base  is  made  between  the  beds  in 
order  to  facilitate  irrigation.  A  ditch  should  be  made  between  each 
two  rows  of  beds.  If  the  beds  are  to  be  sprinkled  instead  of  flooded, 
the  ridges  need  not  be  as  large  as  when  the  former  method  of  irri- 
gation is  used.  The  location  of  these  beds  should  be  such  that  they 
may  be  irrigated  easily  and  sheltered  from  the  winds.  The  soil  should 
be  of  light  character  so  that  it  will  not  pack  when  wet.  No  water 
should  stand  around  the  plants  during  the  rainy  season. 


Planting. — The  time  of  planting  is  dependent  upon  the  section 
of  the  state,  in  which  the  garden  is  located,  the  variety  planted,  and 
the  season  at  which  it  is  desired  to  have  the  crop  mature.  In  central 
California  the  seed  is  generally  planted  during  September  for  the 
early  spring  onions,  or  from  November  until  February,  inclusive,  for 
the  later  crops.  The  seed  may  be  sown  either  in  drills,  having 
the  rows  from  two  to  four  inches  apart,  or  broadcast,  covering  with 
one-half  inch  of  soil.  From  one  to  two  pounds  of  seed  will  grow  a 
sufficient  number  of  plants  for  one  acre,  providing  the  seed  is  of  good 
quality. 

If  it  is  desirable  to  fertilize  the  beds,  finely  screened  stable  manure 
may  be  used  and  should  be  applied  long  enough  in  advance  of  plant- 
ing so  that  it  will  be  completely  rotted  before  sowing  the  seed. 


Fig.  1. — Onion  seed  beds  containing  plants  six  weeks  old. 


Under  ordinary  conditions  the  plants  will  be  ready  to  set  in  the 
field  from  six  weeks  to  two  months  after  the  seed  has  been  sown.  The 
beds  should  be  watched  very  carefully  and  the  moisture  should  be 
continually  kept  at  the  surface.  During  the  early  fall  the  beds  are 
often  irrigated  three  or  four  times  a  week,  especially  during  the  warm 
weather. 


When  the  plants  are  from  one-fourth  to  one-half  an  inch  in 
diameter  at  the  surface  of  the  soil,  they  are  ready  to  be  transplanted 
to  the  field.  At  the  University  Farm  garden  1555  square  feet  of  seed 
beds,  including  irrigation  ditches,  produced  a  sufficient  number  of 
plants  for  one  acre  in  the  field. 

During  the  mid-winter  or  early  spring  planting,  the  hotbeds  may 
be  used  in  preference  to  the  one  above  described.  The  method  of 
planting  and  care  of  the  plants  is  the  same  for  both  types  of  beds. 

Transplanting  to  the  Field. — The  transplanting  is  done  between 
November  and  March,  inclusive,  the  exact  time  depending  largely 
upon  the  date  of  planting  the  seed,  variety  and  the  local  climatic 
conditions. 


"    ■■■■■-■:"■    ■;::;;: ;:~& 


Fig.  2. — Digging  and  trimming  onion  seedlings  preparatory  to  transplanting. 

One  week  before  the  plants  are  to  be  removed  from  the  seed 
beds  the  watering  should  be  discontinued  in  order  that  they  may 
be  well  hardened.  A  few  hours  before  digging,  the  plants  should  be 
thoroughly  irrigated.  They  may  be  dug  with  the  aid  of  a  shovel  or 
spade  and  in  such  a  manner  that  at  least  two  inches  of  the  roots  will 
remain  on  the  plants.  After  digging,  the  plants  are  separated  from 
each  other  and  laid  in  rows  or  piles.     The  tops  should  be  cut  off  to 


the  end  of  the  central  blade  and  the  roots  trimmed  until  they  are 
one-half  inch  to  one  inch  in  length.  From  the  time  they  are  removed 
from  the  beds  until  they  are  transplanted,  the  seedlings  should  be 
covered  in  order  that  as  many  of  the  small  fibrous  roots  as  possible 
may  be  preserved. 


Fig.    3. — Plant   properly   trimmed   for   transplanting. 

The  field  may  be  divided  into  sunken  beds,  setting  the  plants  three 
or  four  inches  apart  in  rows  twelve  to  fifteen  inches  apart.  The 
size  of  the  beds  is  determined  by  the  slope  of  the  land,  but  under 
ordinary  conditions  each  is  twenty  feet  square. 

When  the  cultivation  is  to  be  performed  by  horse-drawn  imple- 
ments, the  rows  should  be  as  long  as  possible.  The  plants  are  set  in 
the  bottom  of  furrows  two  to  three  inches  deep  and  the  roots  may 
be  covered  by  raking  the  earth  over  them. 


The  transplanting  is  done  most  economically  by  three  men,  two 
placing  the  plants  and  the  third  covering.  Under  ordinary  condi- 
tions it  will  take  three  men  three  days  to  plant  one  acre,  provided 
they  do  not  have  to  pull  their  plants. 


CARE    OF    PLANTS    IN    THE    FIELD 

Irrigation. — A  large  percentage  of  the  onions  grown  in  California 
require  irrigation.     The  exact  time  for  applying  the  water  is  depen- 


Fig.  4. — Setting  onion  plants  in  field. 

dent  upon  the  season  of  the  year,  and  the  character  of  the  soil.  If 
the  plants  are  set  in  the  field  in  November,  the  soil  should  be  thor- 
oughly irrigated  before  planting,  provided  there  has  not  been  sufficient 
rainfall.  After  the  plants  have  started  to  grow  they  should  never  be 
allowed  to  suffer  from  lack  of  moisture,  for  if  their  growth  is  retarded 
they  are  liable  to  go  to  seed  or  become  scullions  instead  of  producing 
marketable  bulbs. 

The  number  of  irrigations  which  the  field  should  receive  will  vary 
from  two  to  five,  the  exact  number  being  largely  determined  by  the 
rainfall  and  season. 

In  irrigating  the  field,  care  should  be  taken  not  to  allow  the  water 
to  pass  over  the  ground  too  rapidly ;  it  is  better  to  use  a  small  stream, 


Fig.   5. — Plants  set  in  sunken  beds. 


Fig.  6. — Setting  plants  in  long  rows  to  permit  cultivation  by  horse-drawn 

implements. 


10 


allowing  the  moisture  to  seep  into  the  soil  thoroughly,  than  to  use  a 
large  swift  running  stream.  The  soil  should  be  kept  continuously 
moist  up  to  one  to  three  inches  from  the  surface.  When  the  plants 
are  starting  to  mature  the  watering  should  be  discontinued,  the  soil 
being  allowed  to  dry  out  as  much  as  possible. 

Cultivation. — The  cultivation  is  generally  performed  with  hand 
implements.  The  field  should  be  hoed  from  one  to  five  times,  depend- 
ing upon  the  weed  growth,  character  of  the  soil,  and  the  number  of 
irrigations.     If  the  soil  is  of  a  heavy  texture,  it  should  be  hoed  after 


Fig.  7.- 


-The  cultivation  of  onions  should  be  such  that  no  weeds  will  be 
allowed  to  grow. 


each  irrigation,  but  on  the  more  open  soils  the  time  of  cultivation  is 
governed  largely  by  the  weed  growth. 

Hoeing  should  always  be  shallow  for  if  the  earth  is  disturbed  too 
deeply  near  the  plants,  there  is  liability  of  cutting  off  many  of  the 
roots.  After  the  bulbs  are  one-half  to  two-third  grown  it  is  a  good 
plan  in  hoeing  the  field,  to  place  a  small  amount  of  earth  over  them 
for  protection  against  heat.  This  is  especially  important  during 
mid-summer  in  the  interior  sections  of  the  state. 

Breaking  Down  Tops. — When  the  plants  are  forming  large  necks 
or  seed  stalks  instead  of  bulbs,  the  breaking  over  of  the  tops  a  few 


11 


inches  from  the  ground  is  recommended.  There  are  several  methods 
for  doing  this,  the  choice  depending  largely  upon  the  size  of  the  field. 
In  large  areas  this  may  be  done  by  dragging  a  board  or  rolling  a 
barrel  over  the  tops,  but  in  a  small  garden  they  may  be  broken  by 
stepping  on  them.  If  the  crop  is  growing  normally  this  practice  is 
unnecessary. 

Harvesting.— It  is  very  important  that  the  harvesting  be  done  at 
the  proper  time ;  if  it  is  deferred  too  long  the  crop  will  be  a  partial, 
if  not  a  total  loss,  for  if  the  onions  reach  maturity  and  are  not  pulled 


Fig.  8. 


over  of  the  tops  is  one  ind 
for  harvesting. 


ition  that  the  crop  is  ready 


from  the  ground  they  will  send  out  new  rootlets  in  a  very  short  time, 
especially  if  there  is  an  abundance  of  soil  moisture.  This  second 
growth  is  very  difficult  to  check  and  it  will  make  the  onions  unfit  for 
anything  but  immediate  use.  There  is  also  danger  from  sunburn 
by  leaving  the  mature  bulbs  exposed  during  hot  weather. 

The  customary  period  at  which  to  harvest,  is  when  the  majority 
of  the  tops  of  the  onions  have  begun  to  turn  greenish  yellow.  Unfor- 
tunately all  of  the  onions  will  not  mature  at  the  same  time,  but  it  is 
better  to  harvest  some  before  they  are  wholly  mature  than  to  allow  a 
portion  of  the  crop  to  remain  in  the  field  a  considerable  time  after 
it  has  ripened. 


12 

The  crop  may  be  harvested  by  hand  or  by  the  use  of  some  imple- 
ment. Where  a  small  variety  is  grown  the  former  method  is  generally 
practiced,  but  when  growing  a  large  variety,  such  as  the  Italian  Red, 
it  will  often  be  found  more  advantageous  to  dig  the  crop  by  means  of 
a  hoe  or  certain  implements  which  are  made  especially  for  this  work. 

After  the  onions  have  been  taken  out  of  the  ground  they  are  thrown 
in  windrows  or  piles  in  the  field,  where  they  remain  until  the  tops  are 
completely  dry.  The  length  of  time  they  are  kept  in  these  piles  is 
determined  by  the  degree  of  maturity,  and  the  climatic  conditions. 


: 


(Courtesy  of  A.   Levy  and  J.   Zentner  Co.) 
Fig.  9. — Curing  and  sacking  a  200-acre  field  of  onions. 


In  the  interior  of  the  state,  during  the  warmer  months,  from  three  to 
seven  days  will  be  sufficient,  but  in  the  colder  sections  a  longer  time 
is  often  required. 

After  curing  sufficiently,  the  tops  are  cut  off  from  one-half  to  one 
inch  from  the  bulbs.  In  doing  this  it  will  be  found  most  advantageous 
to  use  a  knife  or  shears  and  care  should  be  taken  not  to  bruise  the 
bulbs. 

After  topping,  the  onions  are  placed  immediate  in  sacks  or  crates 
and  hauled  to  their  shipping  point  or  to  a  shed.  Onions  which  are 
maturing  during  the  spring  and  summer  are  usually  shipped  as  soon 


13 


as  possible,  but  the  crop  which  is  dug  in  the  fall  may  either  be  dis- 
posed of  immediately  or  placed  in  storage. 

The  California  onion  crop  is  marketed  either  in  sacks  holding  100 
to  105  pounds,  or  in  crates  containing  50  pounds  net. 

STORAGE 

A  large  percentage  of  the  onion  crop  is  sold  directly  from  the 
field,  especially  when  it  matures  during  the  spring  and  summer.  If 
it  is  desired  to  grow  a  crop  for  storage,  the  date  of  planting  should 


(Courtesy  of  A.  Levy  and  J.  Zentnei-  Co.) 
Fig.  10. — Method  of  storing  onions  during  the  winter. 

be  late  enough  in  the  spring  so  that  the  onions  will  not  mature  before 
October,  for  it  has  been  found  very  unsatisfactory  to  store  onions 
during  the  warmer  months  unless  they  are  kept  under  constant  refrig- 
eration. If  the  crop  is  harvested  in  October  it  will  be  possible  to 
keep  it  in  satisfactory  condition  up  to  March  or  even  later,  provided 
the  proper  methods  are  used.  Onions  which  are  kept  in  storage  must 
be  protected  from  the  rains  and  from  freezing, 

The  customary  method  for  holding  the  crop  is  by  placing  it  in 
weather-proof  sheds  or  barns.  Such  structures  must  be  well  ventilated 
and  the  onions  may  either  be  placed  in  bins  or  stored  in  sacks. 


14 

During  the  warm  winter  days  the  house  should  be  kept  closed  and 
the  doors  generally  opened  at  night,  providing  the  weather  is  not  too 
severe.  Even  though  the  storage  facilities  are  adequate,  there  will 
often  be  more  or  less  trouble  and  it  is  sometimes  necessary  to  sort 
over  the  onions  one  or  more  times,  throwing  away  all  those  which 
have  started  to  rot  or  sprout,  for  a  few  rotted  onions  will,  under 
moist  conditions  ruin  much  of  the  contents  of  the  sack. 

It  is  only  after  much  experience  that  one  will  be  able  to  hold  a 
crop  in  storage  successfully  for  several  months,  and  as  there  is  con- 
siderable shrinkage  in  weight,  and  the  expense  for  sorting  is  large, 
one  should  not  enter  into  this  phase  of  the  work,  at  least  in  a  large 
way,  without  having  had  some  previous  experience. 


(Courtesy  of  A.   Levy  and  J.  Zentner  Co.) 

Fig.   11. — In  the  delta,  after  sacking,  the  onions  are  hauled  to  the  river  banks 

and  loaded  on  barges. 


ONIONS  AS  A  TRUCK   CROP 

In  the  production  of  onions  in  the  market  gardens  throughout  the 
state,  the  area  varies  from  one  to  five  acres.  Onions  are,  however, 
produced  on  a  more  extensive  scale  and  some  of  the  onion  farms 
comprise  as  many  as  200  acres  or  more. 

Onions  which  are  produced  on  the  truck  farms  are  usually  grown 


15 


from  seed  planted  directly  in  the  field  and  the  rows  are  spaced  far 
enough  apart  so  that  the  cultivation  may  be  done  with  horse-drawn 
implements.  The  seeding  generally  starts  in  January  and  continues 
until  March  or  April.  The  onion  seed  is  planted  by  means  of  drills 
and  the  rows  are  spaced  from  fifteen  inches  to  two  feet  apart.  It  is 
estimated  that  from  three  to  four  pounds  of  seed  will  be  required 
per  acre. 

After  the  plants  are  from  two  to  four  inches  in  height  the  plantings 
should  be  thinned,  leaving  the  space  between  every  two  plants  from 
three  to  four  inches.  At  the  time  of  thinning,  the  field  is  generally 
hand-hoed.  The  water  is  supplied  either  by  running  in  furrows 
between  the  rows  of  plants,  or  by  sub-irrigation. 

The  crop  is  harvested  and  stored  in  the  same  manner  as  when 
grown  in  the  market  garden. 


Fig.   12.— Italian  Red. 


16 


VARIETIES 

California  Red. — A  medium-sized,  flat,  very  early  maturing  variety, 
red  in  color,  of  fair  keeping  quality  and  grown  chiefly  for  its  early 
maturation.     Produced  principally  in  Sacramento  and  delta  sections. 

Stockton  Red. — Very  similar  to  the  California  Red  in  habits  of 
growth  and  appearance.     Grown  principally  in  the  delta. 

Italian  Red. — A  very  large,  red,  medium  early  maturing  variety, 
pear  or  bottle  shape  and  very  sweet.  It  stands  shipment  fairly  well. 
It  is  grown  principally  at  Sacramento. 


Fig.  13. — Yellow  Globe  Danvers. 

Yellow  Globe  Danvers. — Early  maturing,  yellow  in  color,  medium 
size  and  good  in  shipping  quality.  A  very  desirable  variety  to  grow 
on  light  soils.    It  is  grown  in  all  onion-producing  sections  of  the  state. 

Yellow  Flat  Danvers. — Grown  under  similar  conditions  as  the 
Yellow  Globe  Danvers,  but  differs  in  shape. 

South  Port  White  Globe. — A  very  popular  white  variety;  keeps 
well,  and  is  grown  extensively  over  the  state. 

Bermuda. — Very  popular,  early  maturing  variety,  especially  suited 
for  sandy  soil  and  grown  principally  in  southern  California. 

Australian  Brown. — A  very  popular  and  widely  grown  variety, 
especially  adapted  for  fall  maturing  and  storage  in  the  winter;  best 


17 

suited  for  the  delta  sections,  as  the  growth  is  better  on  peat  or  muck 
soils  than  on  those  of  a  drier  nature.  It  is  late  in  maturing  and  a 
general  favorite  on  the  market. 

Back  Skin. — Grown  commonly  in  the  delta  and  resembles  the 
Australian  Brown  in  manner  of  growth,  appearance  and  keeping 
qualities. 

Prize  Taker. — A  large  yellow  onion,  good  keeper  and  recommended 
for  a  fall  crop. 


ONION  SEED  PRODUCTION 

California  has  long  been  recognized  as  the  leading  onion-seed 
producing  state.  The  principal  sections  in  which  this  crop  is  culti- 
vated are  located  in  Santa  Clara,  San  Benito,  Santa  Barbara,  San 
Joaquin,  and  Sacramento  counties. 

During  the  season  of  1917  there  were  5000  acres  devoted  to  onion 
seed  production  in  this  state ;  the  average  planting  during  the  past 
ten  years  has  been  3500  acres.  The  increase  represented  by  these 
figures  is  due  to  the  heavy  demand  for  seed,  owing  chiefly  to  the 
European  conditions;  from  present  indications  there  will  be  a  much 
larger  acreage  planted  during  the  coming  year. 

YIELD,    COST    OF    PRODUCTION,    AND    PRICES    RECEIVED 

The  yield  of  seed  varies  from  300  to  500  pounds  per  acre ;  it  is 
influenced  largely  by  the  climatic  conditions,  and  the  variety.  Occa- 
sionally yields  of  800  to  1000  pounds  per  acre  are  secured,  but  during 
an  unfavorable  season,  in  which  dry  hot  winds  are  prevalent  at  the 
time  the  seeds  are  forming,  the  crop  may  be  a  partial,  or  a  total  failure. 

When  the  bulbs  are  produced  by  the  growers,  the  cost  of  growing 
one  acre  of  onion  seed  will  vary  from  $75  to  $90,  exclusive  of  rent 
or  the  cost  of  fertilization. 

The  prices  paid  for  onion  seed  vary  from  30  to  50  cents  per  pound, 
depending  on  the  variety  and  the  care  of  the  grower. 

CULTURAL    REQUIREMENTS 

Onion  seed  may  be  grown  successfully  on  a  large  variety  of  soils, 
provided  the  latter  are  rich.  Rich  loams,  and  adobe  in  good  physical 
condition  are  commonly  used  for  this  purpose ;  the  peat  soils  are  not 
as  desirable,  as  the  seed  is  liable  to  be  rather  light  and  shriveled. 

The  moisture  requirements  are  similar  to  those  needed  for  grow- 
ing onions  for  the  market. 


18 


GROWING   THE    BULBS 

Onion  seed  is  produced  by  transplanting  the  matured  onion,  and 
the  seed  for  this  crop  should  be  sown  from  February  to  April,  inclusive. 
The  manner  of  production  is  similar  to  that  used  for  growing  onions 
for  the  market.  The  onions  may  be  harvested  during  September  and 
October,  and  cured  and  sacked  preparatory  to  transplanting.  A  bulb 
one-half  to  three-quarters  grown  is  more  commonly  used  for  seed 
production  than  a  large  onion. 


PLANTING  THE   BULBS 

The  bulbs  may  be  planted  in  the  field  from  October  to  February, 
inclusive,  setting  them  six  inches  to  one  foot  apart  in  rows  from  three 
to  four  feet  apart,  the  exact  distance  depending  largely  upon  the 
variety  and  the  size  of  the  bulbs.  The  bulbs  may  be  set  in  the  field 
before  the  rains  commence;  where  a  large  area  is  to  be  grown,  it  is 
better  to  use  this  method  than  to  plant  too  late  in  the  winter. 

Where  more  than  one  variety  is  used,  they  should  be  separated 
from  each  other  and  should  never  be  planted  so  that  the  prevailing 
winds  will  blow  the  pollen  from  one  variety  to  another.  It  is  a  good 
plan  to  grow  some  tall,  quick-growing  crop  such  as  corn  or  sunflowers 
between  every  two  varieties  and  they  should  be  separated  by  at  least 
one  hundred  yards. 

In  the  future  care  of  the  crop  no  weeds  should  be  allowed  to  grow. 
A  good  supply  of  moisture  should  continually  be  present  in  the  soil 
for  if  the  growth  of  the  plants  is  checked  the  yield  will  be  lessened. 
When  the  seed  stalks  are  about  one  foot  tall,  the  earth  should  be  drawn 
toward  the  plants. 

It  is  often  desirable  to  irrigate  the  plants  once  or  twice  during 
the  season  and  this  may  be  done  by  sub-irrigating  or  running  the  water 
in  furrows  between  the  plants,  being  careful  not  to  allow  it  to  run 
over  them.  With  normal  rainfall  it  will  not  be  necessary  to  irrigate 
until  the  seed  stalks  start  to  grow.  If  a  second  irrigation  is  necessary, 
this  should  be  done  before  the  seed  has  developed  in  the  heads. 


HARVESTING 

The  time  to  harvest  is  largely  dependent  on  the  local  conditions, 
but  it  generally  falls  during  July  and  August.  Occasionally  onion 
seed  is  matured  during  the  latter  part  of  June.     It  is  very  important 


19 

that  the  crop  be  harvested  at  the  proper  time,  for  if  the  plants  are 
over  ripe,  much  of  the  seed  will  shatter,  but  should  it  be  harvested 
before  it  is  fully  matured  the  seed  will  be  of  inferior  quality.  The 
proper  time  for  harvesting  is  when  the  seed  cases  are  opening  and 
it  is  often  necessary  to  go  over  the  field  two  or  three  times  before  the 
entire  crop  is  gathered.  The  stalk  should  be  cut  from  one  to  two 
inches  from  the  head,  placed  on  canvas,  thoroughly  dried,  spread  in  a 
layer  two  or  three  feet  deep,  and  separated  from  the  seed  heads.  This 
is  done  by  rolling  with  a  two-horse  roller  or  threshing  machine.     The 


Fig.  14. — Onion  seed  nearing  maturity. 


seed  is  then  run  through  a  blower  or  cleaner  which  will  remove  much 
of  the  chaff  and  some  of  the  undeveloped  light  seed.  It  may  be 
dipped  in  water,  allowing  the  seed  to  remain  submerged  for  a  few 
minutes.  The  light  seed  and  chaff  is  then  scraped  off  from  the  surface. 
The  good  seed  will  be  found  at  the  bottom,  and  should  be  taken  out 
and  dried  on  canvas  immediately  and  sacked.  The  seed  is  not  always 
dipped  in  water  and  unless  the  grower  has  had  previous  experience, 
this  should  be  done  very  cautiously,  for  if  the  seeds  are  submerged  too 
long  they  will  sprout  and  lose  their  value. 


20 


SELECTION    OF  THE    BULBS 

In  order  to  produce  onion  seed  of  good  quality,  it  is  very  important 
that  a  careful  selection  of  the  bulbs  be  made,  using  only  those  which 
conform  to  the  type.  It  is,  therefore,  imperative  that  the  grower  know 
exactly  the  kind  of  onion  which  he  wishes  to  develop  and  the  most 
careful  growers  make  two  selections,  one  to  be  used  for  the  production 
of  the  commercial  seed  and  the  other  for  the  seed  to  be  used  in  the 
future  for  growing  the  bulbs.  The  following  table  illustrates  the 
necessity  of  planting  onion  seed  which  is  not  over  two  years  old ;  seed 
one  year  old  is  preferable : 


Vitality  of  Onion  Seedi 

California-grown  seeds  No.  samples 

viable 

Seed  stated  to  be  less  than  one  year  old 400  88 J  8 

Seed  stated  to  be  between  one  and  two  yearst  old 220  77.46 

Seed  stated  to  be  between  two  and  three  years  old 2,023  57.43 

Seed  stated  to  be  between  three  and  four  years  old 1  10.00 

There  is  an  excellent  opportunity  for  the  production  of  this  crop 
in  California  for  a  grower  who  is  careful  to  produce  seed  of  high 
quality,  but  the  demands  of  the  market  are  becoming  so  exacting  that 
there  is  very  little  encouragement  for  the  careless  seed  grower. 


CROP   TROUBLES 

Under  normal  conditions  the  onion  crop  in  California  is  compara- 
tively free  from  disease  and  insect  pests.  The  following  are  the  most 
common  troubles  which  occasionally  cause  considerable  damage : 

Damping  Off. — This  disease  is  found  in  the  seed  bed  and  may 
attack  the  young  seedlings  at  the  time  they  are  coming  through  the 
surface  and  until  they  have  grown  their  second  pair  of  true  leaves. 
The  plants  wither  and  fall  over  as  if  they  had  been  cut  off  at  the 
surface  of  the  ground.  The  trouble  is  first  noticed  by  the  appearance 
of  a  few  scattered  affected  plants,  but  under  favorable  conditions  the 
disease  will  spread  very  rapidly  through  the  bed.  This  condition  is 
caused  by  several  fungi  which  live  in  the  soil,  and  is  most  common 
during  wet  weather,  especially  if  the  growth  of  the  plants  is  slow. 

After  the  disease  has  become  established,  it  is  very  difficult  to 
control ;  the  following  recommendations  are  suggested  for  avoiding 


i  Biennial  Ker>ort,  Conn.  Agr.  Exp.  Sta.,  1909-1910,  pt.  12,  p.  114. 


21 

this  condition :  Good  drainage,  irrigate  seldom  but  thoroughly  and 
in  the  morning  only,  isolate  the  diseased  plants  by  digging  a  furrow 
four  inches  deep  or  pouring  formalin  around  the  affected  areas.  The 
following  spray  will  also  be  found  advantageous  : 

Bluestone    3  lbs. 

Lump  lime  4  lbs. 

Water    50  gals. 

Mildew. — This  disease  is  troublesome  during  warm,  moist  weather 
and  is  most  commonly  found  in  districts  having  considerable  fog.  It 
attacks  the  stalks  and  leaves,  causing  large  dead  areas  upon  which 
may  be  seen  the  dark  purplish-colored  mildew.  This  is  especially 
troublesome  in  growing  onion  seed  as  the  seed  stalks  fall  over,  and 
development  of  the  seed  stop.  To  quote  Professor  R.  E.  Smith  regard- 
ing the  disease : 

This  disease  has  not  been  successfully  controlled  in  California,  but  in  the 
eastern  states  has  yielded  fairly  well  to*  spraying  with  bordeaux  mixture  to  which 
a  resin  sticker  has  been  added.  This  spraying  must  be  done  at  frequent  intervals, 
commencing  before  the  mildew  appears. 

The  development  of  resistant  strains  by  seed  selection  is  promising.2 

Failure  to  Produce  Bulbs. — Occasionally  a  large  part  of  the  crop 
will  develop  seed  stalks  and  large  neck  onions  or  scullions,  instead  of 
marketable  bulbs.  This  condition  may  be  caused  from  planting  in 
the  wrong  season,  sudden  check  in  the  growth  of  the  plants,  or  poor 
seed.  The  remedy  lies  in"  planting  only  seed  of  good  quality,  and 
irrigating  frequently  enough  so  that  the  growth  may  be  steady  and 
uniform.  When  early  spring  onions  are  desired,  the  plants  should 
not  be  set  in  the  field  before  November;  when  the  seeding  is  done 
directly  in  the  field,  they  should  be  planted  not  earlier  than  December. 
Breaking  over  of  the  tops  or  cutting  off  the  seed  stalks  when  the  crop 
is  maturing  will  correct  this  trouble  considerably. 

Onion  Thrips. — To  quote  Essig  regarding  this  pest : 

The  constant  chafing  of  the  thrips  upon  the  leaves  produces  countless  numbers 
of  small  white  or  silvery  spots  which  are  very  noticeable.  The  growth  of  the 
plant  is  often  stunted  by  the  attacks. 

This  species  of  thrips  is  generally  distributed  throughout  the  entire 
state.  It  is  often  very  troublesome  to  onion  growers  in  the  warm 
interior  valleys  and  in  the  Imperial  Valley. 

2  Calif.  Agr.  Exp.  Sta.,  Bui.  218,  p.  1133. 


22 

Control. — Like  mites,  thrips  are  very  difficult  to  control,  because 
of  their  large  numbers,  exceedingly  small  size  and  the  tender  plants 
which  they  infest.  Many  sprays  will  readily  kill  them  because  of  their 
small  size,  but  the  nature  of  the  host  plant  does  not  always  permit 
such  treatment.  Tobacco  decoctions  and  lime-sulphur  or  oil  emulsions 
give  very  good  results.  The  following  formula  is  recommended  by 
J.  R.  Watson: 

Commercial  lime-sulphur    (33°   Baume)  5%  gals. 

"Black  Leaf  40"   (tobacco  decoction)  14  fluid  ozs. 

Water   200  gals. 

The  addition  of  one  part  of  "Black  Leaf  40"  to  two  thousand  parts  of  an 
oil  emulsion  or  a  miscible  oil  spray  will  also  give  good  results. 

To  spray  a  spreader  composed  of  4  gallons  of  flour  paste  (1  pound  of  flour 
to  each  gallon  of  water  dissolved  to  make  a  paste)  to  every  100  gallons  will 
greatly  aid  and  give  much  better  results  than  if  used  alone.3 


Suppl.  to  Mo.  Bui.  Cal.  State  Comm.  Hort.,  1915,  p.  56. 


STATION  PUBLICATIONS  AVAILABLE  FOR  FREE  DISTRIBUTION 


1897. 

1902. 
1903. 
1904. 
1914. 
1915. 
1916. 
1917. 


REPORTS 

Resistant  Vines,  their  Selection,   Adaptation,   and  Grafting.      Appendix  to  Viticultural 

Report  for  1896. 
Report  of  the  Agricultural  Experiment   Station  for   1898-1901. 
Report  of  the  Agricultural   Experiment   Station  for   1901-03. 
Twenty-second  Report  of  the  Agricultural  Experiment  Station  for  1903-04. 
Report  of  the  College  of  Agriculture  and  the  Agricultural  Experiment  Station. 
Report  of  the  College  of  Agriculture  and  the  Agricultural  Experiment  Station. 
Report  of  the  College  of  Agriculture  and  the  Agricultural  Experiment  Station. 
Report  of  the  College  of  Agriculture  and  the  Agricultural  Experiment  Station. 


No. 
230. 
241. 
242. 
246. 
248. 

250. 
251. 


252. 
253. 

255. 
257. 
261. 

262. 

263. 
264. 
265. 
266. 

267. 
268. 
270. 


No. 
113. 
114. 
115. 
121. 

124. 
126. 
127. 
128. 
129. 
131. 
133. 
135. 
136. 
137. 
138. 
139. 


140. 


142. 

143. 

144. 
147. 
148. 
150. 
151. 
152. 

153. 

154. 

155. 
156. 
157. 
158. 


BULLETINS 
No. 

Enological  Investigations.  271. 

Vine  Pruning  in  California,  Part  I.  272. 

Humus  in  California  Soils.  273. 

Vine  Pruning  in  California,  Part  II. 

The   Economic  Value  of  Pacific   Coast  274. 
Kelps. 

The  Loquat.  275. 

Utilization  of  the  Nitrogen  and  Organic 

Matter    in    Septic    and    Imhoff   Tank  276. 

Sludges.  277. 

Deterioration  of  Lumber.  278. 

Irrigation   and   Soil   Conditions   in  the  279. 

Sierra  Nevada  Foothills,  California.  280. 

The  Citricola  Scale. 

New  Dosage  Tables.  282. 

Melaxuma    of    the    Walnut,     "Juglans 

regia."  283. 

Citrus   Diseases   of   Florida   and   Cuba  284. 

Compared  with  Those>  of  California.  285. 

Size  Grades  for  Ripe  Olives.  286. 

The  Calibration  of  the  Leakage  Meter.  288, 

Cottony  Rot  of  Lemons  in   California. 

A  Spotting  of  Citrus  Fruits  Due  to  the  290. 
Action  of  Oil  Liberated  from  the  Rind. 

Experiments  with  Stocks  for  Citrus.  291. 

Growing  and  Grafting  Olive  Seedlings. 

A  Comparison  of  Annual  Cropping,  Bi- 
ennial Cropping,  and  Green  Manures 
on  the  Yield  of  Wheat. 

CIRCULARS 
No. 

Correspondence  Courses  in  Agriculture.  160. 

Increasing  the  Duty  of  Water.  161. 

Grafting  Vinifera  Vineyards.  162. 

Some    Things    the    Prospective    Settler 

Should   Know.  164. 

Alfalfa   Silage  for  Fattening  Steers.  165. 

Spraying  for  the  Grape  Leaf  Hopper. 

House  Fumigation.  166. 

Insecticide  Formulas.  167. 

The  Control  of  Citrus  Insects.  168. 

Spraying  for  Control  of  Walnut  Aphis. 

County  Farm  Adviser.  169. 

Official  Tests  of  Dairy  Cows.  170. 

Melilotus  Indica. 

Wood  Decay  in  Orchard  Trees.  172. 

The  Silo  in  California  Agriculture.  174. 

The    Generation    of   Hydrocyanic   Acid  175. 
Gas  in  Fumigation  by  Portable  Ma- 
chines. 176. 

The  Practical  Application  of  Improved 

Methods  of  Fermentation  in  Califor-  177. 

nia  Wineries  during  1913  and  1914.  181. 

Practical  and  Inexpensive  Poultry  Ap- 
pliances. 182. 

Control    of    Grasshoppers    in    Imperial 

Valley.  183. 

Oidium  or  Powderv  Mildew  of  the  Vine.  184. 

Tomato  Growing  in  California.  185. 

"Lungworms." 

Round  Worms  in  Poultry.  186. 

Feeding  and  Management  of  Hogs.  187. 

Some  Observations  on  the  Bulk  Hand-  188. 

ling  of  Grain  in  California.  190. 

Announcement  of  the  California  State  191. 

Dairy  Cow  Competition,    1916-18.  192. 

Irrigation   Practice  in   Growing   Small  193. 

Fruits  in  California.  196. 

Bovine  Tuberculosis.  197. 

How  to  Operate  an  Incubator. 

Control  of  the  Pear  Scab.  198. 

Home  and  Farm  Canning. 


Feeding  Dairy  Calves  in  California. 

Commercial  Fertilizers. 

Preliminary  Report  on  Kearney  Vine- 
yard Experimental  Drain. 

The  Common  Honey  Bee  as  an  Agent 
in  Prune  Pollination. 

The  Cultivation  of  Belladonna  in  Cali- 
fornia. 

The  Pomegranate. 

Sudan  Grass. 

Grain   Sorghums. 

Irrigation  of  Rice  in  California. 

Irrigation  of  Alfalfa  in  the  Sacramento 
Valley. 

Trials  with  California  Silage  Crops  for 
Dairy  Cows. 

The  Olive  Insects  of  California. 

Irrigation  of  Alfalfa  in  Imperial  Valley. 

The  Milch  Goat  in  California. 

Commercial  Fertilizers. 

Potash  from  Tule  and  the  Fertilizer 
Value  of  Certain  Marsh  Plants. 

The  June  Drop  of  Washington  Navel 
Oranges. 

The  Common  Honey  Bee  as  an  Agent 
in  Prune  Pollination.      (2nd  report.) 


Lettuce  Growing  in  California. 

Potatoes  in  California. 

White    Diarrhoea    and    Coccidiosis    of 

Chicks. 
Small  Fruit  Culture  in  California. 
Fundamentals    of    Sugar    Beets    under 

California   Conditions. 
The  County  Farm  Bureau. 
Feeding  Stuffs  of  Minor  Importance. 
Spraying  for  the  Control  of  Wild  Morn- 

ing-Glory  within  the  Fog  Belt. 
The  1918  Grain  Crop. 
Fertilizing     California     Soils     for     the 

1918  Crop. 
Wheat  Culture. 
Farm  Drainage  Methods. 
Progress  Report  on  the  Marketing  and 

Distribution  of  Milk. 
Hog     Cholera     Prevention     and     the 

Serum  Treatment. 
Grain  Sorghums. 
Control     of     the     California     Ground 

Squirrel. 
Extending  the  Area  of  Irrigated  Wheat 

in  California  for  1918. 
Infectious  Abortion  in  Cows. 
A  Flock  of  Sheep  on  the  Farm. 
Beekeeping  for  the  Fruit-Grower  »:id 

Small  Rancher,  or  Amateur. 
Poultry  on  the  Farm. 
Utilizing  the  Sorghums. 
Lambing  Sheds. 

Agriculture  Clubs  in  California. 
Pruning  the  Seedless  Grapes. 
Cotton  in  the  San  Joaquin  Valley. 
A  Study  of  Farm  Labor  in  California. 
Dairy  Calves  for  Veal. 
Suggestions    for   Increasing   Egg   Pro- 
duction in  a  Time  of  High-Feed  Prices. 
Syrup  from  Sweet  Sorghum. 


